Ethylene copolymer with improved hygienic property and process for preparing the same
View Patent ↗Provided is an ethylene copolymer having improved hygienic property. More particularly, the ethylene copolymer satisfies a correlation between a density thereof and an extract content. The ethylene copolymer having improved hygienic property can be applied in injection molding, rotation molding, or blow molding.
1. An ethylene copolymer obtained by polymerization of ethylene and a (C3-C18) α-olefin co-monomer, the ethylene copolymer being injection-moldable, wherein the ethylene copolymer has a density of 0.91 to 0.94 g/cm 3 and a melt index (MI) of 3 to 50 g/10 min, a molecular weight distribution index 1.98 to 2.21 as measured by mass average molecular weight divided by number average molecular weight, and satisfies Formulas 1 and 2 below:
S ≧(8×10 56 )× e −144.1D [Formula 1]
S ≦(3×10 25 )× e −61.8D [Formula 2]
in Formulas 1 and 2, S (wt %) represents an extract content of the ethylene copolymer at 35° C. after 10 minutes as measured by temperature rising elution fractionation analysis using 1,2,4-trichlorobenzene as a solvent, and D (g/cm 3 ) represents a density of the ethylene copolymer.
2. The ethylene copolymer of claim 1 , wherein the ethylene copolymer satisfies Formula 1 as defined in claim 1 and Formula 3 below:
S ≦(7×10 32 )× e −81.1D [Formula 3]
in Formula 3, S (wt %) represents an extract content of the ethylene copolymer at 35° C. after 10 minutes as measured by themperature rising elution fractionation analysis using 1,2,4-trichlorobenzene as a solvent, and D (g/cm 3 ) represents a density of the ethylene copolymer.
3. The ethylene copolymer of claim 1 , wherein the extract content (S) of the ethylene copolymer is 1.8 wt % or lower.
4. The ethylene copolymer of claim 1 , wherein the extract content (S) of the ethylene copolymer is 0.1 to 1.8 wt %.
5. The ethylene copolymer of claim 1 , wherein the (C3˜C18) α-olefin comonomer is selected from propylene, 1-butene, 1-pentene, 4-methyl-1-pentene, 1-hexene, 1-octene, 1-decene, 1-dodecene, and a mixture thereof.
6. The ethylene copolymer of claim 5 , wherein the (C3˜C18) α-olefin comonomer is contained in a content of 1 to 40 wt %.
7. The ethylene copolymer of claim 1 , wherein the polymerization is conducted in the presence of a catalyst composition including a transition metal catalyst represented by Chemical Formula 1 below:
in Chemical Formula 1, M represents a group IV transition metal in a periodic table;
Cp is a cyclopentadienyl ring or a fused ring including a cyclopentadienyl ring, which may be η5-bonded to the central metal M, and the cyclopentadienyl ring or the fused ring including a cyclopentadienyl ring may be further substituted with one or more selected from (C1-C20)alkyl, (C6-C30)aryl, (C2-C20)alkenyl, and (C6-C30)ar(C1-C20)alkyl;
R 1 through R 4 independently represent a hydrogen atom, a halogen atom, (C1-C20)alkyl, (C3-C20)cycloalkyl, (C6-C30)aryl, (C6-C30)ar(C1-C10)alkyl, (C1-C20)alkoxy, (C3-C20)alkylsiloxy, (C6-C30)arylsiloxy, (C1-C20)alkylamino, (C6-C30)arylamino, (C1-C20)alkylthio, (C6-C30)arylthio, or nitro, or the R 1 through R 4 are linked to an adjacent substituent via (C3-C12)alkylene or (C3-C12)alkenylene with or without a fused ring to form an alicyclic ring and a monocyclic or polycyclic aromatic ring;
Ar 1 represents (C6-C30)aryl or (C3-C30)heteroaryl containing one or more selected from N, O, and S;
X 1 and X 2 independently represent a halogen atom, (C1-C20)alkyl, (C3-C20)cycloalkyl, (C6-C30)ar(C1-C20)alkyl, (C1-C20)alkoxy, (C3-C20)alkylsiloxy, (C6-C30)arylsiloxy, (C1-C20)alkylamino, (C6-C30)arylamino, (C1-C20)alkylthio, (C6-C30)arylthio, or
R 11 through R 15 independently represent a hydrogen atom, a halogen atom, (C1-C20)alkyl, (C3-C20)cycloalkyl, (C6-C30)aryl, (C6-C30)ar(C1-C10)alkyl, (C1-C20)alkoxy, (C3-C20)alkylsiloxy, (C6-C30)arylsiloxy, (C1-C20)alkylamino, (C6-C30)arylamino, (C1-C20)alkylthio, (C6-C30)arylthio, or nitro, or the R 11 through R 15 are linked to an adjacent substituent via (C3-C12)alkylene or (C3-C12)alkenylene with or without a fused ring to form an alicyclic ring and a monocyclic or polycyclic aromatic ring; and
the alkyl, aryl, cycloalkyl, aralkyl, alkoxy, alkylsiloxy, arylsiloxy, alkylamino, arylamino, alkylthio, and arylthio of R 1 through R 4 , R 11 through R 15 , and X 1 and X 2 ; a ring formed by linking R 1 through R 4 or R 11 through R 15 to an adjacent substituent via alkylene or alkenylene; and the aryl or heteroaryl of Ar 1 may be further substituted with one or more selected from a halogen atom, (C1-C20)alkyl, (C3-C20)cycloalkyl, (C6-C30)aryl, (C6-C30)ar(C1-C10)alkyl, (C1-C20)alkoxy, (C3-C20)alkylsiloxy, (C6-C30)arylsiloxy, (C1-C20)alkylamino, (C6-C30)arylamino, (C1-C20)alkylthio, (C6-C30)arylthio, nitro, and hydroxy.
8. An injection product manufactured from the ethylene copolymer of claim 1 .
9. The injection product of claim 8 , wherein the injection product is a food container.
10. The injection product of claim 8 , wherein the injection product is a container for using in a refrigerator.
11. The injection product of claim 8 , wherein the injection product is a pipe, a hollow molded product, a rotation molded product, or a sheet product.